Is there a list for Keyframe data_paths in Blender?
You can right click the property in the user interface and choose Copy Data Path

You can also key it manually and explore the object's animation data with the outliner using the data block option.



or view it in the graph editor



You might try to create a list yourself:

import bpy

obj = bpy.context.active_object
txt = bpy.data.texts.new("list")
for prop in obj.bl_rna.properties:
    if prop.is_animatable and not prop.is_readonly:
        txt.write(prop.identifier + '\n')
    elif prop.type == "POINTER":
        txt.write("---Pointer--- \n" + prop.identifier + '\n')
        for sub in prop.fixed_type.bl_rna.properties:
            if sub.is_animatable and not sub.is_readonly:
                txt.write(sub.identifier + '\n')
        txt.write("------------- \n")


It is possible to explore the properties with the outliner: